View Full Version : Oil leak, cracked block, what to do?!!
Evening chaps! Long time since I've put a post on here..!
I've been struggling for a while (several years!) with a persistant oil leak under full power and coating the underside with the stuff, sometimes slapping up the rear window. I've never really managed to sort it. Just giving the car a bit of TLC in the shed and decided to tackle the leak assuming it was the sump not sealing properly as I'm planning some track action next month.
Just whipped it off and found the crack in the block as per the pics! Its at the back just next to the flywheel/starter motor. Guessing this is the cause of the leak.
Bit unsure as what to do as the engine runs 100% perfect and its running circa 200bhp @20psi and its strong. Its a fairly recent build with probably less than 10k on it so I'm loathed to pull it out and go hunt out another block.:(
Suggestions....?
Cheers,
Dave
andybond
29-01-2014, 19:19
Haters are going to hate ....
Chemical metal it.
Ran it on a cracked block on an old engine and lasted years. No point stressing over it. Bang some on , if it still leaks you have a automatic rust prevention system.
scratcher
29-01-2014, 19:51
How far up into the block does the crack go?
It's cracked for a reason, it could get worse.
I had exactly the same thing on my raider a few year back I swopped the block in the end it's not worth it dumping all the oil if it gets worse an destroying everything stopping everything into a new block should alter any of the power
Haters are going to hate ....
Chemical metal it.
Ran it on a cracked block on an old engine and lasted years. No point stressing over it. Bang some on , if it still leaks you have a automatic rust prevention system.
Starting to agree!
Kinda thinking/hoping now that its probably nothing to do with the leak I've had and probably nothing to worry about :)
Not sure how far the crack goes up, I was getting bored of the oil dripping in my face...! I'll have a butchers in the morning to see whats what. Guessing someone dropped the block at some point, brittle stuff this cast iron :)
as said previously, depending how far the crack goes up the block, either chemical metal or a bit of shady welding/grinding flat......
All depends how arsed you can be;) nothing to loose by at least trying some chemical metal:agree:
I to would be reluctant to take it apart if it's a good un.
Never seen one crack there before, they normally go round the water jacket at the back of the block near the top, fingers crossed yours hasn't gone there and cracked all the way down:disagree:
Mine has been cracked in the same place for years, goes about 3" up the back of the block. Loads of abuse and its still the same. They regularly crack there, dont worry about it.
as said previously, depending how far the crack goes up the block, either chemical metal or a bit of shady welding/grinding flat......
IF your doing the welding, get it hot before you weld and try to slow the cooling down too....
best/easiest option get the flywheel off, and clean up the block, (crack) and fill it with chemical metal...
Mine has been cracked in the same place for years, goes about 3" up the back of the block. Loads of abuse and its still the same. They regularly crack there, dont worry about it.
All the cracked blocks I have seen are at the top, probably due to hydrolocking headbolts. Wonder what makes them crack down there. :confused:
Crack cleaned! :ashamed:
Blasted it with some IPA and compressed air and then rammed it full with chemical metal. The crack goes up maybe an inch. Think the block must have had a knock, can't see how else it's cracked there.
Got some loctite 5980 to stick the sump on. Must be good stuff cos it takes a week to go off!
Mr Raider
30-01-2014, 23:08
Good job mate, crack doesnt exist anymore ;) :agree:
Just about to put the sump back on, Haynes manual not in sight!
Does anyone have the torque figures to hand for the sump bolts please...? :) :)
Nad-5GTT
01-02-2014, 14:25
Just about to put the sump back on, Haynes manual not in sight!
Does anyone have the torque figures to hand for the sump bolts please...? :) :)
Just been out to shed and the manual doesn't list the sump bolts torque setting :crap: you don't need to go to mad though. Maybe getting just tight then 1/2 a turn again.
Just been out to shed and the manual doesn't list the sump bolts torque setting :crap: you don't need to go to mad though. Maybe getting just tight then 1/2 a turn again.
Thanks mate :) I'll just crack on then!!
Dave
Jobs a goodun! Kettle on! :coffee::D
Woznaldo
01-02-2014, 23:26
Experience is key here and as others have had some experience with cracking in that area, it's probably going to be fine. There are a number of reasons that metals crack. This crack is probably due to tensional stress. In some cases, when the stress continues, the crack will continue to propagate, but in other cases the crack often relieves the stress and therefore the crack growth slows or stops altogether.
The addition of chemical metal may help to stop any further flexing and therefore stop fatigue stress cracking.
Either way, I hope it doesn't rear its head again. :)
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